Temperature correcting apparatus and voltage-controlled oscillation apparatus

ABSTRACT

A temperature correcting apparatus divides an actually measured waveform of correcting voltages, which are required at each of different temperatures, by a minimum resolution of D/A conversion; obtains voltage digital values representing voltage values at individual dividing points of the actually measured waveform, and obtains times corresponding to the voltage digital values; prestores pairs of the voltage digital values and times together with addresses as correcting data; reads out the correcting data in response to the detection address representing the temperature; extracts or calculates from the correcting data the voltage digital values and times about the correcting voltages required by the detection address; and sequentially supplying a D/A converter ( 36 ) with the resultant voltage digital values in synchronization with the corresponding times.

This application is a Divisional of application Ser. No. 10/503,088filed on Jul. 30, 2004 now U.S. Pat. No. 7,248,126, which claimspriority of Japan Application No. 2002-331099 filed Nov. 14, 2002, andfor which priority is claimed under 35 U.S.C. § 120. The entire contentsof each of the above-identified applications are hereby incorporated byreference.

TECHNICAL FIELD

The present invention relates to a temperature correcting apparatus anda voltage-controlled oscillation apparatus for detecting the ambienttemperature of an apparatus to be corrected such as an oscillationcircuit, whose operation is susceptible to the effect of temperature,and for supplying a voltage waveform passing through correctingprocessing to the apparatus to be corrected via a D/A converter.

BACKGROUND ART

An oscillation circuit is a typical temperature sensitive circuit whosenormal operation is impaired by the effect of the ambient temperature.This is because the frequency characteristics of the resonator of theoscillation circuit have temperature dependence such as a cubic curve.Accordingly, it is necessary for the temperature sensitive circuit tocorrect its operation in response to the temperature. A conventionaltemperature correcting apparatus used for this purpose generally detectsthe ambient temperature with a temperature sensor, generates acorrecting voltage in response to the detected ambient temperature, andcarries out correcting control by supplying the correcting voltage tothe apparatus to be corrected such as an oscillation circuit. However,it is necessary for the apparatus to be corrected, which requires highlyaccurate temperature correction over a wide temperature range, tosubdivide the temperature range to make correction of the individualsubdivisions, and to consider the detection error of the temperaturesensor together with the reduction in the effect on the variations inthe detection characteristics of the sensor.

A conventional temperature correcting apparatus meeting the foregoingrequirements is disclosed in Japanese patent application laid-open No.2001-68996. It converts a plurality of temperature detection values toaddresses, corrects the temperature characteristics of the temperaturesensor in response to the individual addresses, and stores thecorrecting addresses in a storage in advance. In addition, it storescorrecting data, which are determined by considering the correctingvoltages for correcting the temperature characteristics of the apparatusto be corrected, in the storage in advance in correspondence to theindividual correcting addresses. Then, it detects the ambienttemperature with a temperature sensor, carries out the A/D conversion ofthe detected temperature value to an address, and reads the correctingaddress corresponding to the converted address. Subsequently, it readsthe correcting data according to the correcting address read out, andD/A converts the correcting data to produce a correcting voltage to befed to the apparatus to be corrected. To achieve highly accuratecorrection by the technique, however, an increasing amount of the D/Adata is required. On the other hand, Japanese patent applicationlaid-open No. 2001-28514 discloses a technique for reducing memorycapacity by storing differential data with respect to a specifiedtemperature into a memory instead of storing all the D/A data.

With the foregoing configuration, the conventional temperaturecorrecting apparatus must consider the quantization error of the D/Aconverter. This is because when the D/A converter generates the voltagewaveform for correcting a given temperature, the data is input atconstant sampling intervals. Thus, to reduce the error of the D/Aconverter, which consists of the quantization error always accompanyingthe quantization, a higher bit D/A converter is required. Thus using thehigher bit D/A converter results in an increase in the amount of the D/Adata and in the cost. On the other hand, Japanese patent applicationlaid-open No. 2001-28514, which calculates the D/A data by thecorrecting calculation, has a problem of bringing about quantizationerror at every voltage output carried out by the D/A conversion atconstant sampling intervals.

The present invention is implemented to solve the foregoing problems.Therefore it is an object of the present invention to provide atemperature correcting apparatus that carries out highly accuratecorrection by curbing the occurrence frequency of the quantization errorof the D/A converter even by using a low bit D/A converter, and thatimplements low cost temperature correcting processing, and avoltage-controlled oscillation apparatus using the temperaturecorrecting apparatus.

DISCLOSURE OF THE INVENTION

According to a first aspect of the present invention, there is provideda temperature correcting apparatus including: a storing unit fordividing an actually measured waveform of correcting voltages, which arerequired by an apparatus to be corrected at each of a plurality ofdifferent temperatures, by a positive integer multiple of a minimumresolution of D/A conversion (the resolution can be represented as 2^(n)in the case of n bits), for obtaining voltage digital valuesrepresenting voltage values at individual dividing points of theactually measured waveform and obtaining times corresponding to thevoltage digital values, for generating a plurality of pairs consistingof the voltage digital values and the times at each temperature ascorrecting data, and for prestoring the correcting data of individualtemperatures in correspondence with addresses representing thetemperatures; temperature sensor means for detecting an ambienttemperature of the apparatus to be corrected and producing a detectionvoltage; A/D converting means for A/D converting the detection voltageto produce detection address representing the temperature; processingmeans for reading out correcting data from the storing unit according tothe detection address, extracting or calculating the voltage digitalvalues about the correcting voltages required by the detection address,and the times corresponding to the voltage digital values from thecorrecting data, and for sequentially outputting the resultant voltagedigital values in synchronization with the times; and D/A convertingmeans for generating correcting voltages to be supplied to the apparatusto be corrected by performing D/A conversion of the voltage digitalvalues output.

According to a second aspect of the present invention, there is provideda temperature correcting apparatus including: a storing unit for storinga plurality of pairs of digital data consisting of pairs of voltage dataand time data corresponding to the voltage data for each of a pluralityof different detection addresses corresponding to a plurality oftemperatures; an A/D converter for carrying out A/D conversion of anambient temperature detected by a temperature sensor, and for outputtinga corresponding detection address through the A/D conversion; aprocessor for sequentially acquiring time data from the storing unitaccording to the detection address output from the A/D converter, andfor sequentially outputting the voltage data corresponding to the timedata at intervals of a positive integer multiple of a minimum resolutionof the D/A converter in response to the timings specified by the timedata acquired; and a D/A converter for carrying out D/A conversion ofthe voltage data output from the processor, and for supplying D/Aconversion results to the apparatus to be corrected.

In this way, the temperature correcting apparatus obtains the voltageoutput based on integer multiples of the minimum resolution 2^(n) of theD/A conversion rather than the voltage output based on the number oftimes of the sampling by using a low-bit D/A converter. In addition, itcan suppress D/A conversion error even after the temperature correctingprocessing. Accordingly, it offers an advantage of being able to carryout highly accurate temperature correcting processing. As a result, ithas an advantage that it can be configured using a low cost D/Aconverter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a circuit configuration of atemperature correcting apparatus of an embodiment 1 in accordance withthe present invention;

FIG. 2 is a graph illustrating a waveform of correcting voltages of theembodiment 1 in accordance with the present invention;

FIG. 3 is a graph illustrating a method of converting an actuallymeasured waveform of the correcting voltages to digital data in theembodiment 1 in accordance with the present invention;

FIG. 4 is a block diagram showing a part of a circuit configuration ofthe temperature correcting apparatus of an embodiment 2 in accordancewith the present invention;

FIG. 5 is a graph illustrating a method of converting an actuallymeasured waveform of the correcting voltages to digital data in theembodiment 2 in accordance with the present invention;

FIG. 6 is a block diagram showing a part of a circuit configuration ofthe temperature correcting apparatus of an embodiment 3 in accordancewith the present invention; and

FIG. 7 is a graph illustrating a method of converting an actuallymeasured waveform of the correcting voltages to digital data in theembodiment 3 in accordance with the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

The best mode for carrying out the invention will now be described withreference to the accompanying drawings to explain the present inventionin more detail.

Embodiment 1

FIG. 1 is a block diagram showing a circuit configuration of atemperature correcting apparatus of an embodiment 1 in accordance withthe present invention. In FIG. 1, an apparatus to be corrected 31 is acircuit whose normal operation is susceptible to the influence of theambient temperature. A temperature correcting apparatus with thefollowing configuration generates a correcting voltage required by theapparatus to be corrected 31 in response to the variations in theambient temperature. The correcting voltage is generated by the D/Aconversion of the temperature correcting apparatus, and has a voltagewaveform 1 as illustrated in FIG. 2, where time intervals of the D/Aconversion are uneven. In FIG. 2, the reference numeral 2 designates avoltage axis graduated in every one LSB of the D/A conversion, and 3designates a time axis.

A temperature sensor (temperature sensor means) 32, which is placed onthe periphery of the apparatus to be corrected 31, detects its ambienttemperature, picks up a detection voltage, and supplies it to an A/Dconverter (A/D converting means) 33. The A/D converter 33 converts thedetection voltage to digital data. The data is fed to a processor(processing means) 35 as a detection address representing thetemperature. The processor 35 has a microcomputer, and includes aread-out section 3511 and a voltage digital value output section(voltage digital value output means) 3521 to carry out the operationwhich will be described later.

A memory (storing unit) 34 stores preset data in the following way. FIG.3 is a graph illustrating a method of converting an actually measuredwaveform of the correcting voltages to digital data. Individual points 9represent voltage values obtained by actually measuring the correctingvoltages, which are required by the apparatus to be corrected at aparticular ambient temperature, at regular intervals in the timedirection. A voltage waveform in an observation range is formed byjoining two adjacent points of the actually measured voltage valuessuccessively by lines 10. The waveform of the correcting voltages isdivided at the LSB intervals of the D/A conversion, and voltages v1, v2,. . . , vn at the individual dividing points (intersections of thedividing lines and the waveform) are converted into digital data with apredetermined number of bits (eight bits, for example), therebyobtaining voltage digital values d1, d2, . . . , dn. In addition, timest1, t2, . . . , tn at the individual intersections, at which the voltagedigital values are acquired, are obtained as the data. Subsequently,pairs (d1, t1), (d2, t2), . . . , (dn, tn) of the voltage digital valuesd1, d2, dn and the corresponding individual times t1, t2, . . . , tn areformed, and all the pairs are made one correcting data, which isprovided with an address and stored in the memory 34. The address isdata representing the temperature, and belongs to the same type of dataas the detection address of the A/D converter 33 representing thedetection temperature of the temperature sensor 32.

FIG. 3 illustrates the actually measured waveform of the correctingvoltages for the particular temperature. For other temperatures, theindividual correcting data are generated in the same manner from theactually measured waveforms, and are stored in the memory 34 with theindividual addresses added to the correcting data.

In the processor 35, the read-out section 3511 reads the correcting datacorresponding to the detection address from the memory 34 according tothe input detection address, and supplies the correcting data to thevoltage digital value output section 3521. The voltage digital valueoutput section 3521 sequentially supplies the D/A converter 36 with thevoltage digital values d1, d2, . . . , dn of the correcting data insynchronization with the times t1, t2, . . . , tn. The voltage digitalvalues are D/A converted by the D/A converter 36, and are generated asthe correcting voltage as illustrated in FIG. 2 via a noise eliminatinglow-pass filter (LPF) 37 and a waveform output section 38 for shaping asmooth analog waveform. The generated correcting voltage is fed to theapparatus to be corrected 31 to perform the temperature compensation ofits operation. The D/A converter 36, low-pass filter 37 and waveformoutput section 38 constitute a D/A converting means in accordance withthe present invention.

As an example, assume that the operation clock of the microcomputer usedas the processor 35 is 5 MHz, the D/A conversion is assigned 8 bit, andthe maximum voltage of the D/A conversion is 5 V in amplitude. Since thesettling time of the D/A conversion is considered to be constant, it ispossible to carry out control in which 1 LSB=5 V/2⁸=5000 mV/256=19.53mV, and the minimum value of the time intervals between adjacent voltagedigital values dn is 200 ns.

Since the voltage data generated by this method are represented usingmultiples of the LSB (2^(n)) of the D/A conversion, it is possible toreduce the occurrence frequency of the quantization error for each LSBof the D/A converter, and to obtain highly accurate output waveform. Forexample, using the 8 bit D/A converter makes it possible to obtain thewaveform equivalent to 10 bit D/A converter in accuracy.

As described above, the embodiment 1 is configured such that it dividesthe actually measured waveform of the correcting voltages, which arerequired by the apparatus to be corrected, at the minimum resolution(LSB) intervals of the D/A conversion for each of the differenttemperatures, obtains the voltage digital values representing thevoltage values at the individual dividing points of the actuallymeasured waveform and the times corresponding to the voltage digitalvalues, generates a plurality of pairs of the voltage digital values andthe times for each temperature as the correcting data, and stores thecorrecting data at the individual temperatures in the memory 34 inadvance in correspondence with the addresses representing the individualtemperatures, and that the processor 35 reads the correcting datacorresponding to the detection address according to the detectionaddress, and sequentially outputs the voltage digital values of thecorrecting data in synchronization with the corresponding times, therebyenabling the D/A converter 36 to generate the voltage waveform. Thus,the present embodiment 1 can generate the voltages in the multiples ofthe minimum resolution 2^(n) using a low-bit D/A converter. Thus, itoffers an advantage of being able to achieve highly accurate correctionwith reducing the occurrence frequency of the quantization error of theD/A converter, and to implement the temperature correcting processingapparatus using low cost memory, microcomputer, D/A converter and thelike because of the reduced data amount.

Embodiment 2

FIG. 4 is a block diagram showing a configuration of the processor ofthe temperature correcting apparatus of an embodiment 2 in accordancewith the present invention; and FIG. 5 is a graph illustrating a methodof converting the actually measured waveform of the correcting voltagesto digital data in the embodiment 2. In the present embodiment 2, atemperature correcting apparatus will be described which uses only twosets of correcting data of two temperatures T1 and T2 as the correctingdata to be prestored in the memory 34.

As for the actually measured waveform 11 of the correcting voltages attemperature T1 and the actually measured waveform 12 of the correctingvoltages at temperature T2 as illustrated in FIG. 5, the correcting dataare generated by the method as described in the foregoing embodiment 1,and are stored in the memory 34 in advance. More specifically, the pairsof the voltage digital values and the times at the temperature T1 are(d11, t11), (d12, t12), (d1 n, t1 n), and the pairs of the voltagedigital values and the times at the temperature T2 are (d21, t21), (d22,t22), . . . , (d2 n, t2 n). These data are stored in correspondence withthe addresses of the temperatures T1 and T2.

When the temperature sensor 32 detects a temperature Tc (where T1<Tc<T2or Tc=T1 or Tc=T2), the detection address obtained by A/D converting thedetection voltage is supplied to the processor 35. A read-out section(read-out means) 3512 reads the data set of the two temperatures T1 andT2 in accordance with the detection address. A coefficient calculatingsection (coefficient calculating means) 353 calculates a temperaturedifference ratio of the temperature indicated by the detection addressfrom the addresses of the set of the two temperatures T1 and T2 and thedetection address as the temperature correcting coefficient.

The temperature correcting coefficient a at the temperature Tc is givenby the following linear approximate expression about the temperatures T1and T2.a=(T1−Tc)/(T1−T2)The coefficient a is given when the ratio of the temperature Tc to thetemperatures T1 and T2 is a: (1−a).

Subsequently, a time calculating section (time calculating means) 354calculates times tcn, at which the voltage digital values dcn (where,dcn=d1 n=d2 n in this case) at temperature Tc are output, from thecoefficient a and the individual times tin and t2 n corresponding to thevoltage digital values d1 n and d2 n (where din=d2 n in this case)indicating the same voltage value in the two correcting data. Using thelinear approximation, the output times tcn on the time axis forperforming the D/A conversion is given by the following expression.tcn=(1−a)×t1n+a×t2n (where n>1)

The times tc1, tc2, . . . , tcn and the voltage digital values dc1, dc2,. . . , dcn sequentially calculated in this way are supplied to avoltage digital value output section (voltage digital value outputmeans) 3522. The voltage digital value output section 3522 sequentiallysupplies the D/A converter 36 with the voltage digital valuescorresponding to the individual output times as the voltage digitalvalues required by the detection address. Thus, the waveform of thecorrecting voltages 13 corresponding to the temperature Tc obtained bythe D/A conversion by the D/A converter 36 and passing through thelow-pass filter 37 and waveform output section 38 has the relationshipswith the voltage waveforms 11 and 12 of the two temperatures T1 and T2as illustrated in FIG. 5. Consequently, the present embodiment 2 canreduce the occurrence frequency of the quantization error of the D/Aconverter or the like for any voltage waveform obtained by thetemperature correction, thereby being able to provide highly accurateoutput waveform.

As described above, the present embodiment 2 is configured such that thememory 34 stores the correcting data of the two different temperaturesT1 and T2 generated in the same manner as in the foregoing embodiment 1,that the processor 35 reads out the correcting data of the twotemperatures T1 and T2 according to the detection address, calculatesthe temperature difference ratio of the temperatures indicated by thedetection address from the addresses of the two read-out correcting dataand the detection address, calculates the output times for carrying outthe D/A conversion from the temperature difference ratio and the timescorresponding to the voltage digital values indicating the same voltagevalues of the two correcting data, and sequentially outputs the voltagedigital values of the same voltage values according to the calculatedoutput times as the voltage digital value required by the detectionaddress. Thus, using the low-bit D/A converter, the present embodiment 2offers an advantage of being able to achieve highly accurate correctionwith reducing the occurrence frequency of the quantization error of theD/A converter, and to implement the temperature correcting processingapparatus using the low cost memory, microcomputer, D/A converter andthe like because of the reduced data amount. In addition, the presentembodiment 2 uses only two sets of prestored data of the differenttemperatures T1 and T2, and calculates the correcting voltagecorresponding to the intermediate detection temperature. Thus, it isapplicable to the case where the temperature range of the location ofthe apparatus to be corrected 31 is narrow, and the upper and lowervalues of the temperature are known in advance. As a result, it offersan advantage of being able to reduce the amount of data to be stored inthe memory.

Embodiment 3

FIG. 6 is a block diagram showing a configuration of the processor ofthe temperature correcting apparatus of an embodiment 3 in accordancewith the present invention; and FIG. 7 is a graph illustrating a methodof converting the actually measured waveform of the correcting voltagesto digital data in the embodiment 3. In the present embodiment 3, thetemperature correcting apparatus uses the correcting data consisting ofa plurality of temperatures T1-Tm as the correcting data to be prestoredin the memory 34, where m is the number of the actually measuredwaveforms of the correcting voltages and is greater than three.

In FIG. 7, reference numerals 21, 22 and 23 designate the actuallymeasured waveforms of the correcting voltages at temperatures T1, T2,and Tm, and 24 and 25 designate the actually measured waveforms of thecorrecting voltages of temperatures Tp and Tp+1, where, p=1, . . . , m.The reference numeral 26 designates the waveform of the correctingvoltages required at the temperature Tc detected by the temperaturesensor 32. As seen from FIG. 7, the temperatures Tp and Tp+1 (Tp<Tc<Tp+1or Tc=Tp or Tp+1) are two adjacent actually measured waveforms of thecorrecting voltages closest to the temperature Tc.

In FIG. 6, when the detection address of the temperature Tc arrives atthe processor 35, a temperature retrieval section (temperature retrievalmeans) 355 retrieves two addresses indicating the two adjacenttemperatures Tp and Tp+1 closest to the temperature Tc indicated by thedetection address from the plurality of addresses in the memory 34 inresponse to the detection address. According to the two retrievedaddresses, a read-out section (read-out means) 3513 reads the correctingdata of the temperatures Tp and Tp+1 corresponding to the two addressesfrom the memory 34. A coefficient calculating section 353 calculates thetemperature difference ratio a of the temperature Tc indicated by thedetection address from the addresses of the correcting data of the twotemperatures Tp and Tp+1 and the detection address in the same manner asin the foregoing embodiment 2.a=(Tp−Tc)/(Tp−Tp+1)

Subsequently, a time calculating section 354 calculates output timestc1, tc2, . . . , tcn for carrying out the D/A conversion from theindividual times tp1, tp2, . . . , tpn, which correspond to the voltagedigital values indicating the same voltage values in the sets of the twotemperatures Tp and Tp+1, and from the temperature difference ratio a bythe following expression.tci=(1−a)×tpi+a×ti+1 (i=1, 2, . . . , n)

According to the calculated output times tc1, tc2, . . . , tcn, avoltage digital value output section 3522 sequentially outputs thevoltage digital values dc1, dc2, . . . , dcn of the same voltage valuesas the voltage digital values required by the detection address. Thewaveform of the correcting voltages corresponding to the temperature Tc,which passes through the D/A conversion by the D/A converter 36 and isobtained via the low-pass filter 37 and waveform output section 38 hasthe relationships with the voltage waveforms 24 and 25 at the twotemperatures Tp and Tp+1 as designated by the reference numeral 26 ofFIG. 7. Preparing a lot of data of the actually measured waveforms ofthe correcting voltages makes it possible to generate the correctingvoltages for the detection temperature at an intermediate position,thereby being able to achieve highly accurate temperature correction. Inaddition, a highly accurate output waveform can be obtained because theoccurrence frequency of the quantization error and the like of the D/Aconverter can be reduced for any voltage waveform after the correction.

As described above, the present embodiment 3 is configured such that thememory 34 prestores the plurality of correcting data generated in thesame manner as in the foregoing embodiment 1, that the processor 35retrieves two addresses indicating two adjacent temperatures closest tothe temperature indicated by the detection address from the plurality ofaddresses in the memory according to the detection address, reads outthe correcting data corresponding to the two addresses in accordancewith the two retrieved addresses, calculates the temperature differenceratio of the temperature indicated by the detection address from theaddresses of the two correcting data read out and the detection address,calculates the output times for carrying out the D/A conversion from theindividual times corresponding to the voltage digital values indicatingthe same voltage values of the two correcting data and from thetemperature difference ratio, and sequentially supplies the D/Aconverter 36 with the voltage digital values of the same voltage valuesaccording to the calculated output times as the voltage digital valuesrequired by the detection address. Thus, the present embodiment 3 canachieve the highly accurate temperature correction by preparing a lot ofdata of the voltage waveforms for the temperature correction in advance.In addition, it offers an advantage of being able to produce a highlyaccurate output waveform by reducing the occurrence frequency of thequantization error of the D/A converter and the like for any voltagewaveform after the correction by using a low-bit D/A converter.Furthermore, it offers an advantage of implementing the temperaturecorrecting processing apparatus using inexpensive memory, microcomputerand D/A converter because the amount of data can be reduced.

Although the foregoing embodiments 1-3 divide the actually measuredvoltage waveform on the LSB unit basis when converting it into thedigital data, this is not essential. For example, the dividing width canbe a positive integer multiple of the LSB, which will presents similaradvantages as easily understood.

Embodiment 4

Recently, Intelligent Transport Systems (ITS) have been developed, whichutilize a vehicle-installed radar for measuring a distance betweenvehicles. A promising millimeter wave radar as the vehicle-installedradar is an FM-CW (Frequency Modulation Continuous Wave) radar. TheFM-CW radar obtains a beat signal including both the distance andvelocity components by supplying a voltage-controlled oscillationapparatus (VCO) with a triangular or sawtooth voltage at a predeterminedperiod for carrying out frequency modulation of a transmission wave, andby mixing a reflected wave from an object with a part of thetransmission wave. The FM-CW radar is suitable as the vehicle-installedradar because its radio frequency circuit for obtaining the beat signaland data processing is rather simple, and it can directly obtain thedistance and velocity signal. Considering severe conditions of vehicleinstallation, however, the voltage-controlled oscillation apparatus issusceptible to the influence of the temperature.

The temperature correcting apparatus described in the embodiments 1-3can be used as a means for generating the triangular or sawtoothcorrecting voltage to be supplied to the voltage-controlled oscillationapparatus operating as the apparatus to be corrected 31, and isapplicable to the temperature correction of the transmission wave of theFM-CW radar. Consequently, the FM-CW radar utilizing the temperaturecorrecting apparatus in accordance with the present invention issuitable for a vehicle-installed product that must satisfy therequirements of high performance and low cost.

INDUSTRIAL APPLICABILITY

As described above, according to the present invention, highly accuratetemperature correcting processing of the voltage-controlled oscillationapparatus can be achieved using the low cost D/A converter. Thereforeapplying it to the vehicle-installed FM-CW radar for measuring thedistance between vehicles is expected to enable it to sufficiently copewith the severe temperature conditions.

1. A temperature correcting apparatus comprising: a storing unit forstoring correcting data for individual temperatures in correspondencewith addresses representing the individual temperatures, the correctingdata for an individual temperature being generated by dividing anactually measured waveform of correcting voltages, which are required byan apparatus to be corrected at the individual temperatures, by apositive integer multiple of a minimum resolution of a D/A converter toobtain times corresponding to voltage digital values representingvoltage values at individual dividing points of the actually measuredwaveform, and generating a plurality of the corresponding times; atemperature sensor for detecting an ambient temperature of the apparatusto be corrected and producing a detection voltage; an A/D converter forA/D converting the detection voltage to a detection address representingthe temperature; a processor for reading out correcting data from saidstoring unit according to the detection address, extracting orcalculating the times corresponding to the voltage digital values fromthe correcting data, and for sequentially outputting the voltage digitalvalues corresponding to the times, in synchronization with the times;and a D/A converter for generating correcting voltages to be supplied tosaid apparatus to be corrected by performing D/A conversion of thevoltage digital values output.
 2. A temperature correcting apparatuscomprising: a storing unit for storing digital data including time datafor each of a plurality of different detection addresses correspondingto a plurality of temperatures; an A/D converter for carrying out A/Dconversion of an ambient temperature obtained by a temperature sensor,and for outputting a corresponding detection address through the A/Dconversion; a processor for acquiring, according to the detectionaddress output from said A/D converter, the digital data correspondingto the detection address from said storing unit, and for sequentiallyoutputting voltage data corresponding to the time data, in response totimings defined by the time data of the digital data acquired; and a D/Aconverter for carrying out D/A conversion of the voltage data outputfrom said processor, and for supplying D/A conversion results to saidapparatus to be corrected, wherein said processor sequentially outputsthe voltage data at intervals of a positive integer multiple of aminimum resolution of said D/A converter.
 3. The temperature correctingapparatus according to claim 1 or claim 2, wherein the apparatus to becorrected is a voltage-controlled oscillation apparatus such that atransmission wave in an FM-CW radar is modulated by a specified voltagewaveform, to be supplied with the correcting voltage of the specifiedvoltage waveform.
 4. The temperature correcting apparatus according toclaim 2, wherein the storing unit stores said digital data as aplurality of pairs of digital data.
 5. The temperature correctingapparatus according to claim 2, wherein the storing unit stores saiddigital data including voltage data corresponding to a plurality oftemperatures.
 6. The temperature correcting apparatus according to claim2, wherein the storing unit stores said digital data as voltage data andtime data for each of the plurality of different detection addressescorresponding to a plurality of temperatures.
 7. The temperaturecorrecting apparatus according to claim 2, wherein the A/D converter forcarrying out A/D conversion converts an ambient temperature detected bythe temperature sensor for outputting a corresponding detection address.8. The temperature correcting apparatus according to claim 2, whereinthe processor for acquiring the digital data acquires pairs of digitaldata corresponding to the detection address from the storing unit. 9.The temperature correcting apparatus according to claim 2, wherein saidstoring unit prestores correcting data of each of two differenttemperatures, and said processor comprises: a read-out section forreading correcting data of each of the two temperatures in response tothe detection address; a coefficient calculating section for calculatinga temperature difference ratio of a temperature indicated by thedetection address from the addresses of the correcting data of the twotemperatures read out and from the detection address; a time calculatingsection for calculating output times for carrying out the D/A conversionfrom the times corresponding to the voltage digital values indicatingsame voltage values of the correcting data of the two temperatures andfrom the temperature difference ratio; and a voltage digital valueoutput section for sequentially outputting the voltage digital values ofthe same voltage values in synchronization with the calculated outputtimes, as voltage digital values required by the detection address. 10.The temperature correcting apparatus according to claim 2, wherein saidstoring unit prestores correcting data of each of a plurality ofdifferent temperatures, and said processor comprises: a temperatureretrieval section for retrieving two addresses representing two adjacenttemperatures closest to a temperature indicated by the detection addressfrom a plurality of addresses in said storing unit in response to thedetection address, a read-out section for reading correcting datacorresponding to the two retrieved addresses according to the twoaddresses; a coefficient calculating section for calculating atemperature difference ratio of a temperature indicated by the detectionaddress from the correcting data of the two temperatures read out andfrom the detection address; a time calculating section for calculatingoutput times for carrying out the D/A conversion from the timescorresponding to the voltage digital values indicating same voltagevalues of the correcting data of the two temperatures and from thetemperature difference ratio; and a voltage digital value output sectionfor sequentially outputting the voltage digital values of the samevoltage values in synchronization with the calculated output times, asvoltage digital values required by the detection address.
 11. Thetemperature correction apparatus according to claim 2, furthercomprising a temperature sensor for detecting an ambient temperature ofthe apparatus to be corrected and producing a detection voltage, and theA/D converter converting the detection voltage to a correspondingdetection address through the A/D conversion.
 12. The temperaturecorrection apparatus according to claim 11, wherein the temperaturesensor is placed on the periphery of the apparatus to be corrected. 13.The temperature correction apparatus according to claim 2, wherein saidstoring unit for storing digital data stores correcting data forindividual temperatures in correspondence with addresses representingthe individual temperatures, the correcting data for an individualtemperature being generated by dividing an actually measured waveform ofcorrecting voltages, which are required by an apparatus to be correctedat the individual temperatures, by a positive integer multiple of aminimum resolution of a D/A converter to obtain voltage digital valuesrepresenting voltage values at individual dividing points of theactually measured waveform and times corresponding to the dividingpoints, and generating a plurality of pairs consisting of the voltagedigital values and the corresponding times.
 14. The temperaturecorrection apparatus according to claim 2, wherein said storing unit forstoring digital data stores correcting data for individual temperaturesin correspondence with addresses representing the individualtemperatures, the correcting data for an individual temperature beinggenerated by dividing an actually measured waveform of correctingvoltages, which are required by an apparatus to be corrected at each ofa plurality of different temperatures, by a positive integer multiple ofa minimum resolution of a D/A converter to obtain voltage digital valuesrepresenting voltage values at individual dividing points of theactually measured waveform and times corresponding to the dividingpoints, and generating a plurality of pairs consisting of the voltagedigital values and the corresponding times at each temperature as thecorrecting data.
 15. The temperature correction apparatus according toany one of claims 4-9, wherein the apparatus to be corrected is avoltage-controlled oscillation apparatus such that a transmission wavein an FM-CW radar is modulated by a specified voltage waveform, to besupplied with the correcting voltage of the specified voltage waveform.